Complex Regional Pain Syndromes

Complex regional pain syndrome (CRPS; reflex sympathetic dystrophy and causalgia) is a heterogeneous chronic pain condition that usually develops following a traumatic injury, usually to an extremity. Although there has been considerable research regarding the mechanisms responsible for pain in CRPS, its pathophysiology remains unclear. The hallmark of CRPS is spontaneous and/or evoked pain. Although signs and symptoms of sympathetic nervous system dysfunction are commonly present, not all patients demonstrate a significant component of sympathetically maintained pain. There is no specific test or finding that is diagnostic of CRPS, and the diagnosis is largely clinical. Treatment of CRPS can be challenging. Management of the patient with CRPS should involve a multidisciplinary approach, and early intervention is important in this regard. The goals of treatment include reduction in pain but, just as important, functional restoration of the affected body part. Management of CRPS includes any combination of pharmacotherapy, physical and occupational therapy, regional anesthetic blocks, behavioral therapies, and surgery. The primary surgical procedures that have been effective for CRPS include spinal cord stimulation, intrathecal drug infusion, and sympathectomy. Surgical intervention is usually most effective earlier rather than later, when patients have developed end-stage CRPS.